Estrada, whom Democrats blocked seven years ago from a post on the federal appeals court in Washington, D.C., wrote a glowing letter recommending Kagan, even while noting that she’s liberal and he’s conservative.

The two sat together as first-year students at Harvard Law School in 1983-84 and remained friends as both swiftly rose in the worlds of law and government. In 2001, Bush nominated Estrada to the bench, but Democrats repeatedly blocked a confirmation vote.

Democrats said Estrada had no judicial experience and complained that he refused to answer questions, noting that the Bush administration wouldn’t release documents from Estrada’s time at the solicitor general’s office. Some of those complaints mirrored Republicans’ objections to Kagan today…